The overall goal of this collaborative Georgia Health Sciences University/Wayne State University renewal submission is to improve the reproductive health of men and women, thereby fostering the birth of healthy, desired children. To achieve this goal the applicants propose to continue to contribute a broad spectrum of research expertise and resources to the Reproductive Medicine Network (RMN). These include a commitment to and track record in cooperative clinical research - e.g., three protocols approved by the RMN Steering and Advisory Committees over the past five years, as well as a superior record of subject enrollment. The two institutions collectively offer an especially large patient base (including an extraordinarily high percentage of minorities) from which to enroll subjects into new and ongoing Network protocols. The concept protocol for the proposed period of support stems from recent secondary analysis of data from the RMN's Pregnancy in Polycystic Ovary Syndrome study, in which the applicants identified a novel outcome: the standard clinical practice of inducing a progestin-withdrawal bleed prior to administration of fertility medications dramatically decreased conception and live birth rates, compared to anovulatory women not treated with progestins. In view of this clear-cut observation, an innovative study has been designed to capitalize on it. The central hypothesis is that progestin administration to induce a withdrawal bleed will have a detrimental effect on live birth outcome in WHO Category II women with a prior anovulatory cycle. To test this hypothesis, we will pursue three specific aims: 1) Determine the rate of live births among such women receiving clomiphene citrate (CC), with or without preceding progestin withdrawal; 2) Concomitantly determine the time to pregnancy in such women; and 3) Determine the influence of progestin withdrawal on the luteal phase hormonal milieu and the endometrium. The expected outcome is that renewal of our membership in the Network would allow continued contribution to the group's cooperative projects, as well as innovation of new research projects for consideration by the group. Coupled with our enlarged joint rural and urban population, documentation of being a major recruiter of racially diverse patients in RMN trials, stellar history of protocol compliance, strong history of oral and written dissemination of RMN results, and personalized attention to mentorship and training of junior clinical investigators, these are expected to have significant positive impact o the Network's capacity to attain its goal of identifying and/or improving diagnostic and therapeutic solutions to problems in reproductive medicine.